Seasonal cycles and winter storms bring extra-high "king tides" that can swamp coastal structures and habitats. What’s a coastal dweller to do? Take pictures! It’s no joke: Educators from the California King Tides Initiative explain how citizen snapshots can be of real value to researchers and policy makers.

Join us as we celebrate the beginning of summer in the Arctic and the long, cold winter in Antarctica. We'll connect live to two polar field sites: Summit Camp atop Greenland's vast ice sheet, where the sun will be shining 24 hours a day, and the South Pole Research Station, now in the middle of 6 months of darkness.

Celebrate the spring equinox at the Mayan ruins of Chichén Itzá, in the state of Yucatan, Mexico. The alignment of the sun on this day creates the appearance of a shadow, in the form of a serpent, that descends the main staircase of the great pyramid. The Live@Exploratorium crew is there to capture the snake on film and to speak with local archaeologists, archeoastronomers, and solar scientists about this amazing phenomenon.

Join the Live@ crew and NASA scientists as we delve into the ancient knowledge of the Chacoans, daily sky watchers who amassed a great knowledge about the movements of the sun. And learn why today's astronomers and solar physicists continue to watch the sun, using modern ground-based observatories and orbiting space telescopes.

Webcasts made possible through the generosity of the Gordon and Betty Moore Foundation, the Jim Clark Endowment for Internet Education, the McBean Family Foundation.

Bandwidth and infrastructure support for connectivity to the California Research and Education Network and to other Internet2-connected networks provided by the Corporation for Educational Networks Initiatives in California (CENIC).